True, but there are activities that will crank up the metabolism a bit and that helps. As I get older, mine has slowed down quite a bit and I have to do the same thing you are doing. I find that the days I do a lot of physical work are the days I drop more than the days I sit around. It doesn't have to be 'exercise'. If I do a lot of yard work or major projects around the house, it helps. I just have to be careful not to snack and ruin what I have lost. I have convince myself that I will feel hungry more than I used to and that's just life. There are worse afflictions, for sure! It is so nice not to have to carry around all that extra weight.
This is how my body works. I can eat all I want and get some sort of exercise and will lose weight. Or I can eat hardly anything, not move as much and the weight will hang on. I was at an event once where it seemed like I was eating something almost all the time. I lost an inch off my waist. Couldn't tell you my weight, since I haven't been near a scale in almost two years.
Your are 100% correct. I am following that plan and am finally losing weight. I’m down now to around 150 and losing. 118 is my target weight. I will get there no matter how long it takes.